Recording system



Aug. 16, 1932. w, LEGG 1,871,709

RECORDING SYSTEM File d June 10, 1927 INVENTOR Joseph W, Legg' T'TORNEY WITNESS Patented Aug. 16, 1932 UNITED STATES PATENT OFFICE JOSEPH W..LEG, OF WILKINSBURG, PENNSYLVANIA, ASSIGNOR TO WESTI IINGHOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

' a constantly rotating light-sensitive surface,"

RECORDING SYSTEM Application filed June 10, 1927. Serial No. 137,983.

My invention relates to an oscillograph or recording system and comprehends a method of and apparatus for producing an oscillogram or record.

In accordance with my invention, operation of a system, as aforesaid, is initiated in response to the occurrence of some event, as one afiecting a characteristic, asthe magnitude, of a quantity; more particularly, the aforesaid event may be a manual control and when the quantity is electrical, it may be a transient, chance or otherwise, precipitating an abnormal circuit condition, as a short circuit, surge of current, abnormal lowvoltage, or the like,

sient or chance transient.

Further in accordance with my invention, movement is imparted to a sensitized surface and thereafter, during continued movement of said surface, an energy-beam is passed into coacting relation therewith while being defiected in accordance with changes in a characteristic of a quantity as effected by the occurrence of an event, as aforesaid.

Further in accordance with my invention, a light-sensitive surface is continuously r0- tated and a beam of light is passed into coacting relation therewith, the beam of light being deflected in accordance with changes in a characteristic of a quantity, particularly an electrical quantity, as current, electromotive force or power, the magnitude of which is changed by the occurrence of a transient.

Further in accordance with my invention, in response to the occurrence of a chance transient, an excessive amount of energy is momentarily supplied to a source of light; from which a beam of l ght passes to a vibrating .mirror and thence to a rotating light-sensitivc surface, whereby there is formed on said surface, beginning immediately after the oc currence of the transient, a record indicative of changes in a characteristic of some quantity.

Further in accordance with my invention, renewed operation of an oscillograph or re.- cording system, particularly one embodying after the lapse of a predetermined interval, is

an event of the character last named being hereinafter termed a tranthe apparatus,

My invention resides in the method, system and apparatus'of the character hereinafter described and claimed.

For an understanding of my method and for an illustration of some of the forms my system may take, reference is to be had to the accompanying drawing, in which:

Figure 1 is a diagrammatic illustration of an oscillograph or recording system constructed in accordance with my invention.

Fig. 2 is a diagrammatic view of a modified circuit arrangement.

Referring to the drawing, there is illustrated a galvanometer mechanism of any suitable character, for example, as disclosed in my prior applications Serial No. 757,586, filed December 23, 1924 or Serial No. 5,166, filed January 27, 1925. As illustrated, the galvanometer mechanism comprises a suitable permanent magnet 1 having spaced pole pieces forminga flux gap 2 into and through which extend the spaced, parallel conductors 3, having a light-reflecting mirror 4 cemented, or otherwise suitably secured thereto. As is well understood in the art and as clearly disclosed in my aforesaid applications, the'conductors 3, should be formed of material having high tensile strength and should be so supported by members, not shown, that they vibrate freely in response to the passage therethrough of a high frequency electrical current.

For passing a beam of light to the mirror 4,

there may be utilized any suitable source of' ror 4 passes through a cylindrical condensing lens 7 and is refracted substantially as a point of light, onto a light-sensitive surface 8 disposed upon a drum or cylinder 9.

In' accordance with my invention, drum 9 and the thereby carried light-sensitive surface 8, are, before and during operation of continuously moved or r0- tated with respect to the beam of light emanating from the mirror 4. Such rotation may be effected in any suitable manner, for example, by securing a pulley 10 to the drum shaft 11, which pulley is driven by a belt 12, in turn driven by a pulley 13 carried by the armature shaft of asuitable electric motor 14.

It shall be understood that the light source 5, the galvanometer mechanism including the mirror 4 and the light-sensitive surface 8 are suitably shielded or protected so that substantially the only light reaching the lightsensitive surface is that transmitted thereto from the mirror 4 or from another desired source or sources.

The vibratory or deflecting system comprising the conductors 3, 3 may be actuated in accordance with a characteristic of any quantity. For example, such quantity may be electrical in character, as current traversing a circuit comprising the line conductors L1 and L2, in which case one of said last named conductors may serve as the primary winding fora current transformer 15, the secondary winding of which has the conductors 16 and 17 connected thereto. Conductors 18 and 19, connected respectively, to the Vibratory system conductors 3, 3 are connected across a non-inductive shunt 20 in cluded in the circuit of conductors 16 and 17 Hence, current traverses the circuit comprising the conductors 18, 3, 3, 19 and the magnitude thereof is proportional to the magnitude of the current induced in the secondary winding of the transformer 15. Since the magnetic fields generated by conductors 3, 3, are angularly related with respect to the flux traversing the gap 2 from the poles of the permanent magnet 1, the

.conductors 3, 3, and the thereto-connected mirror 4 are deflected or vibrated proportionally to the current traversing the line circuit L1, L2, and when the vibratory system is freely responsive to the frequency of the current traversing the conductors 3, 3, the aforesaid deflecting or vibratory movement is proportional-to the instantaneous magnitudes of said current, and hence to the instantaneous magnitudes of the current in the line circuit.

In accordance with my invention, operation of the recording or oscillograph system is initiated in response to the occurrence of some event changing a characteristic of the quantity to which the vibratory system 3, 3 is responsive. Merely by way of illustration, the operation of the recording or oscillograph system is shown as controlled by or depending upon the magnitude of the current traversing the line circuit.

To this end and as illustrated. the circuit comprising the conductors 16'and 17 may include an adjustable resistance 21 across a portion of which is connected the energizing winding of a suitable quick-acting relay 22,

the armature or solenoid of which in the example shown, comprises a conductive contact member 23 adapted when the winding of relay 22 is energized, to move into engagement with a set of fixed contacts 24 and 25. As illustrated, fixed contact 24 is connected by a conductor 26 to one terminal of the aforesaid filament 5, the other terminal of which has connected thereto a conductor 27 leading to one terminal of a suitable capacity area 28, the other terminal of which is connected by a conductor 29, to the aforesaid contact member 23 of relay 22.

A battery 30, or other suitable source of current, has one terminal. connected by a conductor 31 through an adjustable resistance 32 to the aforesaid conductor 27 which, as stated, connects one terminal of'the capacity area 28 to one terminal of the filament 5. The other terminal of battery 30 is connected by a conductor 33 to a conductive contact member 34 of a relay 35. Coacting with the contact member 34, in the example shown, are a set of fixed contacts 36 and 37 the former being connected by a conductor 38 to the contact 25 and the latter to the conductor 26 which, as stated, is connected to the fixed contact 24 of the relay 22.

Branching from the conductor 38 is a conductor 40 which includes, in series arrangement, the winding of relay 35, a resistance 41, and a second resistance 42 which may be an incandescent, or a tungsten filament lamp. Conductor 40 is connected to conductor 31 or to the same terminal of battery 30 to which said last named conductor is connected.

Branching from the conductor 40 is a conductor 43 connected, in the example shown, to the fixed end of a suitable bi-metallic element 44, the movable end of which coacts with a conductive support conductively re-' lated to a conductor 45, one end of which is conductor 40 and comprises awinding or coil 47 in suitable heat-exchanging relation with respect to the bi-metallic element 44. The other end of conductor 46 is connected to the aforesaid conductor 45. v

The aforesaid conductors 29 and 33 have the respective ends of a conductor 48 secured thereto which includes a suitable circuit-rupturing structure, as a fuse 49, and a battery 50 of substantially less potential than the battery 30.

The operation is as follows;

Motor 14 is placed in operation and thereafter rotation of drum 9 and light-sensitive surface 8 continues without pause. Upon occurrence of excessive current in the line circuit L1, L2, as effected by a chance transient or otherevent, the current in the secmember 23 moves into engagement with its coactmg set of fixed contacts 24, 25 and at contact 24 completes the circuit of condenser '28 ,across the terminals of filament 5. The

capacity of condenser 28 is such that an ex.- cessive quantity of energy is momentarily supplied to filament 5, whereby it is quickly brought to substantially normal brilliancy so that a beam of light is passed to the mirror 4 and thence to the moving light-surface 8 without the lapseof appreciable time after the energization of relay 22.

When the contact member 23 of the relay 22 moved into engagement with its coacting fixed contacts 24, 25, a circuit was completed from one terminal of battery 30 through the conductor 33, conductor 48, battery 50, fuse 49, conductor 29, contact member 23, fixed contact 24, conductor- 26, filament 5, conductor 27, conductor 31 and the resistancev 32, then back to the other terminal of battery 30. As soon as condenser 28 is discharged, battery 30 over the circuit last-mentioned, main- .tains filament 5 in its incandescent condition, resistance 32 being so adjusted that the voltage across the terminals of filament 5 is of the'desired value.

When relay 22 was energized as aforesaid, a second circuit was completed from one terminal of battery 30, conductor 33, conduc-' ,tor 48, battery 50, fuse 49, conductor 29, con- -'tact plate 23, fixed contact 25, conductor 38,

conductor 40 including the winding of relay 35 and resistance. 41 and 42, and thence back to the other terminal of battery 30. As a result, relay 35 was actuated and its member .34 moved into engagement with the fixed contacts 36 and 37.

This last-named action of relay 35 has a three-fold effect on the circuit arrangement.

First, a supplementary circuit is completed for the battery 30 through the filament 5. This circuit is as follows: From one terminal of battery 30, conductor 33, contact member 1 34, fixed contact 37, conductor 39, conductor 26, filament 5, conductor 27, conductor 31, and resistance 32, then back to the other terminal of battery 30.

Second, a locking circuit for'the relay 35 is completed from one terminal of battery 30, conductor 33, contact member 34, fixed contact 36, conductor 38, conductor 40, including the winding of relay 35 and resistances 41 and 42, then back to the other terminal of battery 30.

Third, the establishment of a short-circuit by way of conductor 38 across the battery 50, as a result of which the fuse 49 is demolished.

With the circuit in the condition last described, filament 5 remains incandescent to produce a record on the light-sensitive surface 8, even though the current in the line conductors L2, L1 diminishes to an extent permitting deenergization of relay 22, since the relay 35 is closed and maintains the various circuits in their operating condition.

In accordance with my invention, relay 35 v is maintained in its energizedcondition for a predetermined period, usually equal to approximately one revolution of the photographic drum, the length of said period, however, preferably, is adjustable at will. To this end, a part of the current flowing over the aforesaid locking circuit for the relay 35 is shunted around the winding of relay 35 by the conductor 46, winding 47 and conductor 45. After the lapse of a predetermined period and due to the heat generated by Winding 47, the bimetallic element 44, changes its configuration and at its movable end, engages that end of conductor 45 removed from resistance 41. As a result, the winding of relay 35 is short-circuited with consequent deenergization of said relay. Obviously, the movable contact of conductor 45 may be so adjusted with respect to resistance 41 that the current flowing in the shunt circuit assumes any desired value, whereby relay 35 remains ener ized for any desired period.

The incan escent lamp 42, when utilized, serves many urposes. For example, when its filament is of tungsten, the resistance thereof is less when cold than when hot and, therefore, the initial current passing through conductor to produce operation of relay 35 is of relatively large ma itude; lamp 42 may also serve as a signato indicate to an operator or attendant that operationof the recording system has been effected; furthermore, in the event that relay 35 should stick and not move when deenergized by bimetallic element 44, lamp 42 remains lighted and thereby indicates that the apparatus is not functioning properly; still further, in the event that contact 45 is moved entirely to the left, Fig. 1, short circuit of battery 30 is prevented when element 47 closes upon its contact.

A recording system of the character herein described is designed for but one automatic operation. When the circuit interrupting device or fuse 49 was demolished, as aforesaid, the charging circuit for condenser 28, the battery circuit for the filament 5 through fixed contact 24, and the energized circuit for relay 35 through fixed contact 25 was destroyed. Subsequent operation of the system may not then be effected until a new fuse 49 has been placed in position.

' In those cases where filament 5 is designed for a current of one-half ampere at about four volts, the capacity of condenser 28 should be 20 micro-farads, more or less, the battery 30 for charging said condenser and for maintaining filament 5 incandescent, after discharge of condenser 28, having a voltage of the order of 110 volts. It shall be understood, however, that filament 5 and condenser 28 may have such other voltage or current requirements as may be found desirable. Ordinarily; the voltage of battery is substantially less than that of battery 30, and when battery 30 is of the order of 110 volts, the

voltage of said battery may be of the order of ductor 40 terminates in a contact adj ustably coacting with a resistance '56 connected to the aforesaid heating coil. Furthermore, in Fig. 2, the heating coil 47 is connected in parallel relation solely with respect to the Winding of relay 35 and does not shunt a part of the resistance 41 as in Fig. 1.

Accordingly, a greater range of adjustment is obtained in that the entire voltage of battery 30 may be connected across heating coil 47 whereas in Fig. 1 the resistance 42 is always connected in the circuit including heating coil 47 and battery 30. Moreover, resistance lamp 42 may be connected as shown in Fig. 2 to prevent short circuit of the battery30 when bimetallic element 44 closes upon its contact.

In the example illustrated, a record is formed on the light-sensitive surface'8 indicative of the instantaneous magnitudes of current traversing the line L1, L2. It'shall be understood, however, that' the conductors 3, 3, of the vibratory system may be traversed by current varying in magnitude in accordance with a characteristic of any quantity which it may be desirable to observe. Thus, a quantity other than the current of the line circuit, for example, voltage, may be observed.

It shall also be understood that operation of the recording system may be effected otherwise than in response to excessive current in the line circuit. Thus, for example, operation of said system may be effected in response to abnormal high or low voltage thereacross, or otherwise as may be found desirable. y

In lieu of galvanometer mechanism of the character hereindescribed, there may be utilized galvanometer mechanism of the character disclosed in my co-pending application, Serial No. 182,653, filed April 11, 1927, which discloses a vibratory system actuated in accordance with the magnitude of a plurality of factors jointly contributing to the production of another factor.

I claim as my invention:

1. In a recording system having a lightsensitive surface and means for imparting continuous rotative movement to said surface a deflecting system including a mirror con rolled in accordance with a characteristic of a quantity, a source of light for passing a beam of light to said mirror and thence to said surface, means responsive to the occurrence of'an event affecting said characteristic. for energizing said source of light, a disabling device for said last named means actuated in response to the occurrence of said event, and means effective at the termination of a predetermined period for deenergizing said source of light.

, 2. In a recording system having a lightsensitive surface and means for imparting continuous rotative movement to said surface, a deflecting system including a mirror controlled in accordance with a characteristic of a quantity, a source of light for passing a beam of light to said mirror and thence to said surface, means responsive to the occurrence of an event afi'ecting said characteristic for momentarily supplying an excessive quantity of-energy to said source of light and for thereafter supplying energy at a reduced rate, a disabling device for said last named means actuated in response to the occurrence of said event, and means comprising a temperature responsive device effective at the termination of a predetermined period for deenergizing said source of light.

3. In a recording system having a lightsensitive surface on a drum and means for continuously rotating said drum, a deflecting system including a mirror controlled in accordance with a characteristic of a quantity,

means including a source of light for passing a beam of light to said mirror and thence to said surface, relay means responsive to the occurrence of an event afiecting said characteristic for energizing said source of light through a circuit, and means actuated in response to said relay means for maintaining said source of light energized for a predetermined length of time and for disabling said relay means.

4:. In a recording system having a lightsensitive surface on a drum and means for continuously rotating said drum, a deflecting system including a mirror controlled in accordance with a characteristic of a quantity, means including a source of light for passing a beam of light to said mirror and thence to said surface, relay means responsive to the occurrence of an event affecting said characteristic for energizing said source of light through a circuit, and means actuated in response to said relay means for maintaining said source of light energized for a predetermined length of time and for disabling said relay means, said last-named means including means for blowing a fuse.

5. In a recording system having a lightsensitive surface on a drum and means for continuously rotating said drum, a deflecting system including a mirror controlled in accordance with a characteristic of a quantity. means including a source'of light for mssing a beam of light to said mirror and thenceto said surface, relay means responsive to the occurrence of an event afiecting said characteristic for energizing said source of light through a circuit, and means including a hold-in rela for energizing said source of light throug an additional circuit for a predetermined length of time in response to the actuation of said relay means, and for permanently breaking said first-named circuit.

6. Inarecordingsystemhavingalight-sensitive surface on a drum and meansfor continuously rotating said drum, a deflecting system including a mirror controlled inaccordance with a characteristic of a quantity, means including a source of light for passing a beam of light to said mirror and thence to said surface, relay means responsive to the occurrence of an event afiecting said characteristic for energizing said source of light through a circuit, means including a hold-in relay for energizing said source of light through an additional circuit for a predetermined length of time in response to the actuation of said relay means, and means including a source of current and a fuse for breaking said first-named circuit.

In testimony whereof, I have hereunto subscribed my name this 2nd day of June, 1927. JOSEPH W. LEGG. 

